21529141 has 4 divisors (see below), whose sum is σ = 22054284. Its totient is φ = 21004000.

The previous prime is 21529133. The next prime is 21529169. The reversal of 21529141 is 14192512.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2788900 + 18740241 = 1670^2 + 4329^2 .

It is a cyclic number.

It is not a de Polignac number, because 21529141 - 2³ = 21529133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21529171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262510 + ... + 262591.

It is an arithmetic number, because the mean of its divisors is an integer number (5513571).

Almost surely, 2^21529141 is an apocalyptic number.

It is an amenable number.

21529141 is a deficient number, since it is larger than the sum of its proper divisors (525143).

21529141 is an equidigital number, since it uses as much as digits as its factorization.

21529141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525142.

The product of its digits is 720, while the sum is 25.

The square root of 21529141 is about 4639.9505385295. The cubic root of 21529141 is about 278.1904608951.

The spelling of 21529141 in words is "twenty-one million, five hundred twenty-nine thousand, one hundred forty-one".